World Resorts USA Siesta Key Weather

Siesta Key Sea Temperature in September

Average sea water temperature in September:
+85.8°F
Minimum sea water temperature in September: 88.2°F
Maximum sea water temperature in September: 83.1°F

Daily sea water temperature in September, °F

Show year:
2025
2024
2023

The average sea water temperature in September of 2025 was 84.9°F. The highest and lowest sea temperatures during the month were 86.7°F and 83.3°F.

Monthly sea water temperature in Siesta Key, °F

Which USA resorts have warmest sea in September?

Place name September 2025 September 2024
Key West 86.9°F 87.4°F
Islamorada 86.7°F 87.3°F
Key Largo 86.6°F 87.1°F
Fort Lauderdale 86.4°F 86.4°F
Everglades 86.2°F 87.0°F
Miami Beach 86.1°F 86.3°F
Naples 86.1°F 87.2°F
South Padre Island 86.0°F 85.8°F
Corpus Christi 85.8°F 84.7°F
Miami 85.8°F 86.0°F
Sanibel Island 85.7°F 87.0°F
Cape Coral 85.2°F 86.5°F
Houston 84.9°F 83.4°F
Siesta Key 84.9°F 86.8°F
Sarasota 84.8°F 86.7°F
Cocoa Beach 84.6°F 85.2°F
Tampa 84.3°F 86.0°F
New Orleans 84.3°F 82.9°F
St. Petersburg 84.1°F 86.1°F
Mobile 84.0°F 83.5°F

Best time for vacation in Siesta Key

Sunniest months:
March 20 days
May 18 days
April 17 days
Warmest months:
July 88.1 °F
August 88.0 °F
June 86.3 °F
Warmest sea temp:
August 87.6 °F
July 87.1 °F
September 85.8 °F
Coldest months:
January 66.6 °F
December 70.1 °F
February 71.0 °F
Rainiest months:
June 5 days
July 4 days
September 3 days
Windiest months:
November 10.5 mph
January 10.4 mph
October 10.4 mph

Siesta Key on a weather map

Siesta Key
+57°F
W 7 mph
Feels like: +57°F
Precip.: 0%
Places in USA:
Name
°F
+36°F
+75°F
+75°F
+50°F
+55°F
+66°F
+73°F
+70°F
+36°F
+57°F
+57°F
+57°F
+54°F
+70°F
+25°F
24 Hours Forecast
Siesta Key
Local time: 05:26
December 21, sunday
0600
57°F
W
7 mph
0900
64°F
SW
7 mph
1200
70°F
SW
6 mph
1500
73°F
SE
6 mph
1800
73°F
SE
9 mph
2100
72°F
S
11 mph
December 22, monday
0000
68°F
SW
14 mph
0300
66°F
SW
14 mph
Units of measurement: °C / °F